The great wall of china is a series of fortifications made of stone , brick , tamped earth , wood and other materials generally built along an east to west line across the historical northern borders of china to protect the chinese states and empires againist the raids and invasions of the various nomadic groups of the eurasian steppe . Apart from defense other purposes of the great wall have included border controls allowing the imposition of duties on good transported along the silk road regulation or encouragement of trade and the control of immigration and emigration. In 220 b.c . under emperor qin shi huang of china sections of earlier fortifications were joined together to form what we call the great wall today . Construction continued up to the ming dynasty ( 1368 – 1644 ) and the name great wall was actually given in 1877 . The great wall stretches from dandong in the east to lop lake in the west along the arc that roughly delineates the southern edge of inner mongolia. The great wall is not only because of the ambitious character of the undertaking but also the perfection of its construction an absolute masterpiece. The only work built by human hands on this planet that can be seen from the moon the wall constitutes on the vast scale of a continent a perfect example of architecture integrated into the landscape. About one forth of the length of the wall consists solely of natural barriers such as rivers and mountain ridges . Nearly all of the rest ( about 70 percent of the total length ) is actually constructed wall with the small remaining stretches constituting ditches or moats .There is a section of the great wall where it goes up extremely steep slopes in jinshanling and is one of the most striking section of the wall , though earth and stone are mostly the materials used to build the wall glutinous rice ( sticky rice ) was put on the mortar. The amylopectin which makes this rice sticky can probably take credit for the endurance of the wall over the thousands of years. While many portions near beijing have been renovated some parts of the wall have disappeared over the years . It was included under the new seven wonders of the world in 2007 and a unesco world heritage site in 1987 .